Register memory regions reserved by UEFI as IORESOURCE_MEM resources, so that they are reserved for other uses, and also makes them turn up in /proc/iomem.
Signed-off-by: Ard Biesheuvel <[email protected]> --- drivers/firmware/efi/virtmap.c | 36 ++++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) diff --git a/drivers/firmware/efi/virtmap.c b/drivers/firmware/efi/virtmap.c index d1f1d416944f..98735fb43581 100644 --- a/drivers/firmware/efi/virtmap.c +++ b/drivers/firmware/efi/virtmap.c @@ -13,6 +13,7 @@ #include <linux/rwsem.h> #include <linux/spinlock.h> #include <linux/atomic.h> +#include <linux/bootmem.h> #include <asm/efi.h> #include <asm/pgtable.h> @@ -52,6 +53,39 @@ static pgprot_t efi_md_access_prot(efi_memory_desc_t *md, pgprot_t prot) return pgprot_device(prot); } +static __init void efi_register_mem_resource(efi_memory_desc_t *md) +{ + struct resource *res, *parent; + + res = alloc_bootmem_low(sizeof(*res)); + res->start = md->phys_addr; + res->end = res->start + (md->num_pages << EFI_PAGE_SHIFT) - 1; + res->flags = IORESOURCE_MEM; + + if (md->type == EFI_MEMORY_MAPPED_IO && + (md->attribute & EFI_MEMORY_RUNTIME)) { + /* + * Device regions with the EFI_MEMORY_RUNTIME attribute + * are owned by the UEFI firmware, so make sure they are + * tagged as exclusive: this will also prevent access + * via /dev/mem if CONFIG_STRICT_DEVMEM is in effect. + */ + res->name = "UEFI Runtime I/O"; + res->flags |= IORESOURCE_EXCLUSIVE; + } else { + res->name = "UEFI Reserved"; + } + + /* + * Try to register this resource at the top level. If it conflicts with + * an existing entry ('System RAM', most likely), register it as its + * child instead. + */ + parent = request_resource_conflict(&iomem_resource, res); + if (parent) + request_resource(parent, res); +} + void __init efi_virtmap_init(void) { efi_memory_desc_t *md; @@ -63,6 +97,8 @@ void __init efi_virtmap_init(void) u64 paddr, npages, size; pgprot_t prot; + if (!efi_mem_is_usable_region(md)) + efi_register_mem_resource(md); if (!(md->attribute & EFI_MEMORY_RUNTIME)) continue; if (WARN(md->virt_addr == 0, -- 1.8.3.2 -- To unsubscribe from this list: send the line "unsubscribe linux-efi" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
